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A169738 Base 10 numbers d_1 d_2 ... d_k such that the digits d_i are distinct and not zero, and Sum_{i=1..k-1} d_i^i = d_k^k. 1
42, 93, 253, 712, 6312, 9823, 714523, 781523 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..8.

EXAMPLE

6312 is in the sequence because 6^1+3^2+1^3=2^4, and 781523 is in the sequence because 7^1+8^2+1^3+5^4+2^5=3^6.

MATHEMATICA

okQ[l_List] := Module[{lp= l^Range[Length[l]]}, Plus @@ Most[lp] == Last[lp]]

Sort[FromDigits/@Select[Flatten[Table[Permutations/@Subsets[Range[9], {i} ], {i, 2, 9}], 2], okQ]]

CROSSREFS

Sequence in context: A044561 A169680 A177772 * A063329 A172465 A235109

Adjacent sequences:  A169735 A169736 A169737 * A169739 A169740 A169741

KEYWORD

nonn,base,fini,full

AUTHOR

Harvey P. Dale, May 01 2010, May 04 2010

STATUS

approved

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Last modified December 19 17:37 EST 2014. Contains 252238 sequences.